A diet of mostly raw animal foods for cats was examined back in the 1930s by Francis Pottenger, MD. In a ten-year-long study nearly a thousand cats were fed the same basic diet of milk, meat and a small dose of cod liver oil.2
The healthiest cats were the ones who received raw meat and raw milk. This was the only group to produce generation after generation of healthy kittens with broad faces, adequate nasal cavities, broad dental arches, strong and correctly shaped teeth and bones, excellent tissue tone, good-quality fur with a minimum of shedding and an absence of gum disease. These cats were resistant to infections, fleas and internal parasites. They showed no sign of allergies and were gregarious, friendly and predictable in their behavior patterns. Miscarriages were rare and litters averaged five kittens, the mothers nursed without difficulty.
Another group received raw milk and cooked meat. The cats in this group developed skeletal and dental deformities, heart problems, vision problems, thyroid imbalances, infections of the kidney, liver, testes, ovaries and bladder, arthritis and inflammation of the joints, and inflammation of the nervous system with paralysis and meningitis. Their second and third generations had abnormal respiratory tissues. Cooked-meat cats were irritable that some of the females while the males were docile and passive. Vermin and intestinal parasites abounded and skin lesions and allergies appeared frequently. Adult cats died of pneumonia or infections of the bone while kittens died of pneumonia and diarrhea. The cooked-meat cats had serious reproductive problems including sterility, miscarriage, a lack of maternal instinct and difficult labors with high infant mortality rates. Many females died in labor.
The cats fed raw meat with pasteurized milk showed similar changes, and those fed evaporated milk showed even more damage, while the most marked deficiencies occurred among those fed sweetened condensed milk.
Because the health of each new generation was adversely affected by its parents’ inferior diet, the cooked-food kittens had even more problems, and there were no fourth generation kittens in any of the cooked-food groups because the third generation always died before reproducing. Had antibiotic drugs been available, these kittens might not have died of pneumonia and other infectious diseases, in which case the experiment could have continued through longer chains of deformed offspring.
One of Dr. Pottenger’s most exciting discoveries was that the health deterioration caused by cooked foods can be reversed, although it took four generations to completely restore perfect health to cats whose ancestors ate cooked meat or pasteurized milk.